Universal discriminant for continuous-wave operation of laser diodes

We propose a simple and powerful criterion for defining continuous-wave (CW) operation of laser diodes. Our criterion is represented by a quasi-triangular region in the plain spanned by dimensionless parameters α and β. These parameters, deduced from the characteristics of the laser diode operating under pulsed current injection, represent the effects of the turn-on voltage and the series resistance on the increase in the CW threshold. We demonstrate the validity of our criterion using blue-green lasers made from II-VI semiconductors as examples